﻿/*******************************************************
Copyright © 2008-2009 Active Technologies Group, Inc. (ATGi)

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*******************************************************/
using System.IO;
using System.Security.Permissions;

namespace ATGi.CS.Components
{
    public interface IFileSystemWrapper
    {
        void CreateDirectory(string path);
        void DeleteDirectoryIfExists(string path);
        bool DirectoryExists(string path);
        
        void DemandFileIOPermission(FileIOPermissionAccess access, string path);
        
        bool FileExists(string path);
        Stream FileOpenRead(string path);
        void WriteStreamToFile(Stream stream, string filePath);        
    }

    class FileSystemWrapper : IFileSystemWrapper
    {
        public void CreateDirectory(string path) { Directory.CreateDirectory(path); }
        public void DeleteDirectoryIfExists(string path)
        {
            if (Directory.Exists(path))
                Directory.Delete(path, true);
        }
        public bool DirectoryExists(string path) { return Directory.Exists(path); }

        public bool FileExists(string path) { return File.Exists(path); }
        public Stream FileOpenRead(string path) { return File.OpenRead(path); }
        public void DemandFileIOPermission(FileIOPermissionAccess access, string path)
        {
            FileIOPermission permission = new FileIOPermission(access, path);
            permission.Demand();
        }
        
        public void WriteStreamToFile(Stream stream, string filePath)
        {
            // Write the stream to a temporary file.
            using (FileStream fs = File.OpenWrite(filePath))
            {
                byte[] buffer = new byte[32 * 1024]; // 32 KB is a good balance between speed and memory usage.
                int read;

                while ((read = stream.Read(buffer, 0, buffer.Length)) > 0)
                    fs.Write(buffer, 0, read);
            }
        }
    }
}
